Surgical stapler with expandable jaw

ABSTRACT

Jaw assemblies for a surgical stapler are provided. The jaw assemblies comprise a first jaw having a first clamping surface and a plurality of staples disposed therein and second jaw assembly having a second clamping surface. The jaw assemblies can be actuated from a closed configuration in which the first clamping surface contacts or is adjacent to the second clamping surface to an open configuration in which the second jaw is pivoted away from the first jaw to a stapling position in which the second clamping surface is parallel to the first clamping surface and spaced apart from the first clamping surface. A pivoting link or sliding pivot joint can couple the second jaw to the first jaw to facilitate motion between the closed position, the open position, and the stapling position.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/211,570, entitled “SURGICAL STAPLER WITH EXPANDABLE JAW,” filed Mar.14, 2014, which claims the benefit of U.S. Provisional PatentApplication Ser. No. 61/793,065, entitled “SURGICAL STAPLER WITHEXPANDABLE JAW,” filed on Mar. 15, 2013. The entireties of these priorapplications are hereby incorporated herein by reference.

BACKGROUND OF THE INVENTION Field of the Invention

The present application relates generally to surgical occlusioninstruments and, more particularly, to surgical staplers.

Description of the Related Art

Surgical staplers are used to approximate or clamp tissue and to staplethe clamped tissue together. As such, surgical staplers have mechanismsto ensure that tissue is properly positioned and captured and to drivestaples through the tissue. As a result, this has produced, for example,multiple triggers and handles in conjunction with complex mechanisms toprovide proper stapling of the clamped tissue. With these complexmechanisms, surgical staplers can have increased manufacturing burdens,as well as potential sources for device failure and confusion for theuser. Thus, reliable stapling of clamped tissue without complexmechanisms is desired.

SUMMARY OF THE INVENTION

In certain embodiments, a surgical stapler is provided herein. Thesurgical stapler comprises an elongate shaft, a handle assembly, anactuation mechanism, and a jaw assembly. The elongate shaft has aproximal end and a distal end and defines a longitudinal axis betweenthe proximal end and the distal end. The handle assembly is disposed atthe proximal end of the elongate shaft. The actuation mechanism isactuatable by the handle assembly. The actuation mechanism comprises anactuation beam extending through at least a portion of the elongateshaft. The jaw assembly is disposed at the distal end of the elongateshaft. The jaw assembly comprises a first jaw, a second jaw, and aplurality of staples positioned in the first jaw. The first jaw definesa first clamping surface. The second jaw defines a second clampingsurface. The jaw assembly is actuatable by longitudinal movement of theactuation beam between a closed position in which the first clampingsurface contacts the second clamping surface, an open position in whichthe second clamping surface extends at an angle transverse to the firstclamping surface, and a stapling position in which the first clampingsurface extends parallel to the second clamping surface and is spacedapart from the second clamping surface.

In certain embodiments, a surgical stapler is provided herein. Thesurgical stapler comprises an elongate shaft, a handle assembly, anactuation mechanism, and a jaw assembly. The elongate shaft has aproximal end and a distal end and defines a longitudinal axis betweenthe proximal end and the distal end. The handle assembly is disposed atthe proximal end of the elongate shaft. The actuation mechanism isactuatable by the handle assembly. The actuation mechanism comprises anactuation member extending through at least a portion of the elongateshaft. The actuation member comprises a first guide and a second guidethereon. The jaw assembly is disposed at the distal end of the elongateshaft. The jaw assembly comprises a first jaw, a link, and a second jaw.The first jaw extends distally from the distal end of the elongateshaft. The first jaw comprises a first guide slot extendinglongitudinally therein. The link has a proximal end and a distal end.The link comprises a second guide slot having a ramped opening profileformed therein. The proximal end of the link is pivotably coupled to thedistal end of the elongate shaft. The second jaw extends distally fromthe distal end of the link. The second jaw is pivotably coupled to thedistal end of the link. The second jaw comprises a third guide slotextending longitudinally therein. A plurality of staples is disposed inthe first jaw. The first guide is slidable in the first guide slot andthe second guide is slidable in the second guide slot and the thirdguide slot. Translation of the second guide distally over the rampedopening profile of the second guide slot pivots the link away from thefirst jaw to define an open position of the jaw assembly.

In certain embodiments, a surgical stapler is provided herein. Thesurgical stapler comprises an elongate shaft, a handle assembly, anactuation mechanism, and a jaw assembly. The elongate shaft has aproximal end and a distal end and defines a longitudinal axis betweenthe proximal end and the distal end. The handle assembly is disposed atthe proximal end of the elongate shaft. The actuation mechanism isactuatable by the handle assembly. The actuation mechanism comprises anactuation member extending through at least a portion of the elongateshaft. The actuation member comprises a first guide and a second guidethereon. The jaw assembly is disposed at the distal end of the elongateshaft. The jaw assembly comprises a first jaw, a second jaw, and aplurality of staples. The first jaw extends distally from the distal endof the elongate shaft. The first jaw comprises a first guide slotextending longitudinally therein and a first clamping surface. Thesecond jaw comprises a second guide slot and a second clamping surface.The second guide slot extends in the second jaw. The second guide slothas an opening segment with a ramped profile and a stapling segmentextending generally longitudinally distal of the opening segment. Thesecond jaw is slideably coupled to the distal end of the elongate shaftsuch that it is movable between a closed position in which the firstclamping surface contacts the second clamping surface and a staplingposition in which the first clamping surface is parallel to and spacedfrom the second clamping surface. The second jaw is pivotably coupled tothe distal end of the elongate shaft such that the first jaw ispivotable from the closed position to an open position in which thesecond clamping surface extends at an angle transverse to the firstclamping surface. The first guide is slidable in the first guide slotand the second guide is slidable in the second guide slot such thattranslation of the second guide distally through the open segment of thesecond guide slot slides and pivots the second jaw from the closedposition to the open position, and translation of the second guidedistally through the stapling segment positions the second jaw in thestapling position.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an embodiment of surgical staplingdevice with the jaws in an open configuration;

FIG. 2 is a perspective view of an embodiment of cartridge including anelongate shaft and a jaw assembly for the surgical stapling device ofFIG. 1 with the jaws in a closed configuration;

FIG. 3 is a top view of an embodiment of jaw assembly for use in asurgical stapler with the jaws in a closed configuration;

FIG. 4 is a cross-sectional side view of the jaw assembly of FIG. 3;

FIG. 5 is a detailed cross-sectional side view of the jaw assembly ofFIG. 3;

FIG. 6 is a detailed cross-sectional end view of the jaw assembly ofFIG. 3;

FIG. 7 is a cross-sectional side view of the jaw assembly of FIG. 3 withthe jaws in an open configuration;

FIG. 8 is a detailed cross-sectional side view of the jaw assembly ofFIG. 3 with the jaws in the open configuration;

FIG. 9 is a cross-sectional side view of the jaw assembly of FIG. 3 withthe jaws in a firing configuration;

FIG. 10 is a detailed cross-sectional side view of the jaw assembly ofFIG. 3 with the jaws in the firing configuration;

FIG. 11 is a top view of an embodiment of jaw assembly for use in asurgical stapler with the jaws in a closed configuration;

FIG. 12 is a side view of the jaw assembly of FIG. 11;

FIG. 13 is a cross-sectional side view of the jaw assembly FIG. 11;

FIG. 14 is a side view of the jaw assembly of FIG. 11 with the jaws inan open configuration;

FIG. 15 is a cross-sectional side view of the jaw assembly of FIG. 11with the jaws in the open configuration;

FIG. 16 is a side view of the jaw assembly of FIG. 11 with the jaws in afiring configuration;

FIG. 17 is a cross-sectional side view of the jaw assembly of FIG. 11with the jaws in a firing configuration;

FIG. 18 is a top view of an embodiment of jaw assembly for use in asurgical stapler with the jaws in a closed configuration;

FIG. 19 is a side view of the jaw assembly of FIG. 18;

FIG. 20 is a cross-sectional side view of the jaw assembly of FIG. 18;

FIG. 21 is a side view of the jaw assembly of FIG. 18 with the jaws inan open configuration;

FIG. 22 is a cross-sectional side view of the jaw assembly FIG. 18 withthe jaws in the open configuration;

FIG. 23 is a side view of the jaw assembly of FIG. 18 with the jaws in afiring configuration;

FIG. 24 is a cross-sectional side view of the jaw assembly of FIG. 18with the jaws in the firing configuration;

FIG. 25 is a top view of an embodiment of jaw assembly for use in thesurgical stapler with the jaws in a closed configuration;

FIG. 26 is a side view of the jaw assembly of FIG. 25;

FIG. 27 is a side cross-sectional view of the jaw assembly of FIG. 25;

FIG. 28 is a side view of the jaw assembly of FIG. 25 with the jaws inan open configuration;

FIG. 29 is a side cross-sectional view the jaw assembly FIG. 25 with thejaws in the open configuration;

FIG. 30 is a side view of the jaw assembly of FIG. 25 with the jaws in afiring configuration;

FIG. 31 is a cross-sectional side view of the jaw assembly of FIG. 25with the jaws in the firing configuration;

FIG. 32 is a top view of an embodiment of jaw assembly for use in asurgical stapler with jaws in a closed configuration;

FIG. 33 is a side view of the jaw assembly of FIG. 32;

FIG. 34 is a cross-sectional side view of the jaw assembly of FIG. 32;

FIG. 35 is a side view of the jaw assembly of FIG. 32 with the jaws inan open configuration;

FIG. 36 is a cross-sectional side view of the jaw assembly of FIG. 32with the jaws in the open configuration;

FIG. 37 is a side view of the jaw assembly of FIG. 32 with the jaws in afiring configuration;

FIG. 38 is a cross-sectional side view of the jaw assembly of FIG. 32with the jaws in the firing configuration;

DETAILED DESCRIPTION OF THE INVENTION

With reference to FIGS. 1-2, an embodiment of surgical stapling deviceis illustrated. The illustrated embodiment of surgical stapler 10comprises an elongate shaft 20, a jaw assembly 30, and a handle assembly40. FIG. 1 illustrates the surgical stapler 10 with the jaw assembly 30in an open configuration. FIG. 2 illustrates a removable cartridge ofthe surgical stapler 10 with a jaw assembly 30 in a closedconfiguration.

With continued reference to FIGS. 1 and 2, the illustrated embodiment ofsurgical stapler 10 can be sized and configured for use in laparoscopicsurgical procedures. For example, the elongate shaft 20 and jaw assembly30 can be sized and configured to be introduced into a surgical fieldthrough an access port or trocar cannula. In some embodiments, theelongate shaft 20 and jaw assembly 30 can be sized and configured to beinserted through a trocar cannula having a relatively small workingchannel diameter, such as, for example, less than 8 mm. In otherembodiments, elongate shaft 20 and jaw assembly 30 can be sized andconfigured to be inserted through a trocar cannula having a largerworking channel diameter, such as, for example, 10 mm, 11 mm, 12 mm, or15 mm. In other embodiments, it is contemplated that certain aspects ofthe surgical staplers described herein can be incorporated into asurgical stapling device for use in open surgical procedures.

With continued reference to FIGS. 1 and 2, as illustrated, the elongateshaft 20 comprises a generally tubular member. The elongate shaft 20extends from a proximal end 22 to a distal end 24. Elongate shaft 20defines a central longitudinal axis, L, of the surgical stapler 10extending between the proximal end 22 and the distal end 24.

With continued reference to FIGS. 1 and 2, in the illustratedembodiment, the jaw assembly 30 is coupled to the elongate shaft 20 atthe distal end 24 of the elongate shaft 20. The jaw assembly 30comprises a first jaw 32 and a second jaw 34 pivotally coupled to thefirst jaw 32. In the illustrated embodiment, the first jaw 32 is fixedto the distal end 24 of elongate shaft 20 such that it extends distallyalong the central longitudinal axis, L and remains stationary withrespect to the elongate shaft 20. In other embodiments, it iscontemplated that the jaw assembly 30 is articulable with respect to theelongate shaft 20. In an initial configuration, the first jaw 32includes a plurality of staples 36 disposed therein. In someembodiments, staples can be initially positioned in the second jaw 34.

With continued reference to FIGS. 1 and 2, in the illustratedembodiment, the jaw assembly 30 can be actuated from an openconfiguration (FIG. 1) to a closed configuration (FIG. 2) to a staplingconfiguration by an actuation member or beam that is longitudinallyslidable within the elongate shaft. In an initial position, the beam canbe positioned at the distal end 24 of the elongate shaft 20. With thebeam in the initial position, the second jaw 34 is pivoted away from thefirst jaw 32 such that the jaw assembly 30 is in the open configuration.The actuation beam engages the second jaw 34 upon translation of theactuation member or beam distally along the longitudinal axis L.Translation of the actuation beam distally from the initial position afirst distance can actuate the jaw assembly from the open configurationto the closed configuration. With the jaw assembly 30 in the closedconfiguration, the actuation beam can be returned proximally the firstdistance to return the jaw assembly 30 to the open configuration. Adistal end of the actuation beam can advance a staple slider configuredto deploy staples from the first jaw 32 such that further translation ofthe actuation beam distally past the first distance deploys theplurality of staples 36 from the first jaw 32.

With continued reference to FIGS. 1 and 2, in the illustratedembodiment, the handle assembly is coupled to the elongate shaft 20 atthe proximal end 22 of the elongate shaft 20. As illustrated, the handleassembly 40 has a pistol grip configuration with a housing defining astationary handle 42 and a movable handle 44 or trigger pivotablycoupled to the stationary handle 42. It is contemplated that in otherembodiments, surgical stapler devices including aspects described hereincan have handle assemblies with other configurations such as, forexample, scissors-grip configurations, or in-line configurations. Asfurther described in greater detail below, the handle assembly 40 housesan actuation mechanism configured to selectively advance an actuationshaft responsive to movement of the movable handle 44.

In some embodiments, the surgical stapler 10 can include the pluralityof staples 36 positioned in a disposable cartridge while the handleassembly 40 is configured to be reused with multiple staple cartridges.In the illustrated embodiment, the elongate shaft 20 and jaw assembly 30define a disposable cartridge that is removably couplable to the handleassembly 40. Accordingly, in the illustrated embodiment the handleassembly 40 includes a coupler 46 at the distal end thereof. The coupler46 is adapted to engage the elongate shaft 20 of the surgical stapler 10The coupler 46 can a bayonet connection having an outer connector thatcan removably couple to handle assembly 42 the elongate shaft 20, and aninner connector that can removably couple the actuation shaft of thehandle assembly 42 to the actuation member of the elongate shaft 20.Accordingly, the surgical stapler 10 can be configured such that thehandle assembly 40 can be reused with multiple disposable cartridgesduring a surgical procedure. It is contemplated that in otherembodiments, the handle assembly and some portion of the elongate shaftcan be reusable while a remainder of the elongate shaft in the jawassembly define a disposable cartridge. In certain other embodiments,the handle assembly and the elongate shaft can be reusable while the jawassembly defines a disposable cartridge. In still other embodiments, ajaw insert housing a plurality of staples can define a disposablecartridge while the remainder of the surgical stapler is reusable.

As discussed above, surgical staplers 10 described herein can be sizedand configured for insertion into a surgical site through a relativelysmall diameter trocar cannula such as a so-called 5 mm trocar cannulahaving a working channel inner diameter smaller than about 8 mm.Desirably, jaw assemblies configured for insertion through a 5 mm trocarcannula efficiently employ the relatively limited working space toposition both jaws, a plurality of staples, and staple firing elements.In a jaw assembly for a typical laparoscopic surgical stapler, with thejaw assembly in a closed or firing configuration, the first jaw isspaced apart from the second jaw by a gap to accommodate tissue clampedtherebetween when the stapler is in use. However, in a jaw assemblyconfigured for insertion through 5 mm trocar cannula, this spacing ofthe first jaw from the second jaw in the closed position can undesirablybe wasted working space. Accordingly, it can be desirable to configureoperation of a jaw assembly configured for insertion through a 5 mmtrocar cannula such that the gap that would otherwise be wasted workingspace is repurposed to enhance stapling performance. For example, in ajaw assembly configured to eliminate the gap, the otherwise wastedworking space can be repurposed to provide larger staples or more robuststaple driving hardware. In various embodiments, jaw assemblies areprovided herein that reduce or eliminate the gap between the first jawand the second jaw in a closed configuration such that the working spaceof a relatively small diameter surgical stapler can be maximized.

With reference to FIGS. 3-10, an embodiment of jaw assembly 130 isillustrated. FIG. 3 illustrates a top view of the jaw assembly 130 withthe jaws in a closed configuration, and FIGS. 4-6 illustratecross-sectional views of the jaw assembly 130 in the closedconfiguration. In the illustrated embodiment, the jaw assembly 130comprises a first jaw 102 having a first clamping surface 104, a secondjaw 106 having a second clamping surface 108, and a link 112. The firstjaw 102 extends distally from the distal end 24 of the elongate shaft 20(FIGS. 1-2) and is fixed to the elongate shaft 20. The second jaw 106 ispivotably coupled to the first jaw 102. In the illustrated embodiment,the second jaw 106 is pivotably coupled to the distal end 24 of theelongate shaft 20 by the link 112. For example, the link 112 can extendfrom a proximal end, which is pivotably coupled to the distal end 24 ofthe elongate shaft 20, such as with a pinned connection to a distal end,which is pivotably coupled to the second jaw 106, such as with a pinnedconnection.

An actuation mechanism is operably coupled to the handle assembly 40 andactuatable by the movable trigger 44 to actuate the jaw assembly 130 inan open/closed mode, in a firing mode, and in a reverse mode. The jaws102, 106 of the jaw assembly 130 are thus actuatable between a closedconfiguration in which the first clamping surface 104 of the first jaw102 is in contact with or is immediately adjacent to the second clampingsurface 108 of the second jaw 106, an open configuration in which thesecond clamping surface 108 extends at an angle transverse to thelongitudinal axis L away from the first clamping surface 104, and astapling or firing configuration in which the second clamping surface108 is substantially parallel to the first clamping surface 104 and isspaced therefrom. With the jaws in the stapling or firing configuration,a plurality of staples can be deployed from the first jaw 102 throughtissue positioned between the first and second jaws 102, 106 and formedagainst the second clamping surface 108 of the second jaw 106. In someembodiments, the actuation mechanism includes an actuation member suchas an actuation beam 150 that is longitudinally slidable in the elongateshaft 20. The actuation beam 150 can include a first guide 114 and asecond guide 116 formed thereon.

With reference to FIG. 6, in some embodiments, a distal end of theactuation beam 150 comprises an ‘I-beam’ cross sectional profile withthe first and second guides 114, 116 being defined by the horizontalsegments of the ‘I,’ and the vertical segment of the ‘I’ comprising theactuation beam 150. In other embodiments, the actuation member or beamcan have another guide configuration. For example, the guides cancomprise posts, tabs, or other projections extending from the actuationmember.

With reference to FIGS. 4-5, the first jaw 102 can comprise a firstguide slot 118 configured to receive the first guide 114 of theactuation beam 150 in sliding engagement. As illustrated, the firstguide slot 118 can extend generally longitudinally distally from thedistal end 24 of the elongate shaft 20.

With continued reference to FIGS. 4-5, in the illustrated embodiment,the link 112 can comprise a second guide slot 120 formed therein. Thesecond guide slot 120 can extend from a proximal end to a distal end ofthe link 112 and can include an initial closed segment at the proximalend of the link 112, an opening segment distal the closed segment, and afiring transition segment at the distal end of the link 112.

With reference to FIGS. 4-8, the open segment has a curved or angularprofile oriented such that distal sliding of the second guide 116through the second guide slot 120 distal of the initial closed segmentpivots the link 112 (and the second jaw 106 pivotably coupled thereto)away from the first jaw 102 to actuate the jaw assembly 130 from aninitial closed position in which the jaw assembly has a relatively lowdiameter for insertion into a surgical port to an open position forreceiving tissue between the first and second jaws 102, 106. In someembodiments, the link 112 can be biased away from the first jaw 102. Forexample, as illustrated, the jaw assembly 130 can comprise at least onespring 160 biasing the link 112 away from the first jaw 102. This biascan tend to engage the second guide 116 with the opening segment of thesecond guide slot 120 and position the second jaw 106 in the openposition (FIGS. 7-8).

With reference to FIGS. 9-10, once tissue has been positioned betweenthe first jaw 102 and the second jaw 106 in the open configuration at adesired stapling position, the actuation member 150 can be furtheradvanced distally to position the jaws 102, 106 of the jaw assembly 130in a stapling or firing configuration. Further distal movement of theactuation beam 150 advances the second guide 116 over the firingtransition segment of the second guide slot 120 of the link 112 to pivotthe second jaw to a position spaced apart from the first jaw apredetermined distance. The predetermined distance can be selected basedon a desired tissue type for stapling in a procedure or a given staplegeometry. Further distal movement of the actuation member 150 causes thesecond guide 116 to be received in a third guide slot 122 disposed inthe second jaw 106. The third guide slot 122 can include a chamfer,radiused edge, or another transition feature to facilitate thetranslation of the second guide 116 distally from the second guide slot120 to the third guide slot 122. Movement of the second guide 116 overthe transition feature can further pivot the second jaw 106 such thatthe second clamping surface 108 is parallel to the first clampingsurface 104.

As illustrated, the third guide slot 122 extends generallylongitudinally along the second jaw 106 generally parallel to the secondclamping surface 108 such that further distal advancement of the secondguide 116 within the third guide slot 122 maintains the parallelorientation of the first and second clamping surfaces 104, 108 in thefiring configuration. In other embodiments, it is contemplated that thethird guide slot can extend along a curvilinear path or a path extendingtransversely to the second clamping surface 108 to generate a clampingforce between the first and second clamping surfaces 104, 108 as theactuation member 150 is advanced distally.

With reference to FIGS. 9-10, in some embodiments, a distal end of theactuation member 150 can engage a staple driver. As the actuation member150 is advanced distally with the jaws 102, 106 of the jaw assembly 130in the firing position, the staple driver can deploy staples from thefirst jaw 102. The staple driver can include a cutting blade configuredto cut tissue between rows of staples deployed by the jaw assembly.

With reference to FIGS. 11-17, another embodiment of jaw assembly 230for use with a surgical stapler 10 is illustrated. In the illustratedembodiment, the jaw assembly 230 comprises a first jaw 202 having afirst clamping surface 204 and comprising a first guide slot 218, a link212 comprising a second guide slot 220, and a second jaw 206 having asecond clamping surface 208 and comprising a third guide slot 222. Anactuation member 250 or beam comprising a first guide 214 and a secondguide 216 can actuate the jaw assembly 230 from the closed configuration(FIGS. 11-13), to the open configuration (FIGS. 14-15) to the firing orstapling configuration (FIGS. 16-17) in a sequence of operationsubstantially as described above with respect to the jaw assembly 130 ofFIGS. 3-10.

With reference to FIG. 14, unlike the jaw assembly 130 of FIGS. 3-10,the second jaw 206 of the jaw assembly 230 is directly biased away fromthe first jaw 202. For example, in the illustrated embodiment a spring260 is coupled to the first jaw 202 and the second jaw 206 to bias thesecond jaw 206 away from the first jaw. Additionally, the jaw assembly230 includes a pivotal stop 231 preventing excess pivoting of the secondjaw 206 relative to the first jaw 202. In the illustrated embodiment,the second jaw 206 can comprise an extension such as an arm that extendsproximally past the pivotal coupling of the second jaw 206 to the link212. The extension can be sized and configured to engage the first jaw202 when the jaw assembly 230 is positioned in the open configuration tointerfere with further pivoting of the second jaw 206 away from thefirst jaw 202.

With reference to FIGS. 18-24, an embodiment of jaw assembly 330 for usewith a surgical stapler 10 having a sliding pivot point is illustrated.In the illustrated embodiment, the jaw assembly 330 comprises a firstjaw 302 having a first clamping surface 304 and comprising a first guideslot 318 and a second jaw 306 having a second clamping surface 308 andcomprising a second guide slot 320. An actuation member 350 or beamcomprising a first guide 314 and a second guide 316 can actuate the jawassembly 330 from the closed configuration (FIGS. 18-20), to the openconfiguration (FIGS. 21-22) to the firing or stapling configuration(FIGS. 23-24) in a sequence of operation similar to those describedabove with respect to the jaw assemblies 130, 230.

With reference to FIGS. 20-23, in the illustrated embodiment of jawassembly 330, the second jaw 306 is coupled to the first jaw 302 withoutan intercoupled link 112, 212 therebetween. Rather, the jaw assembly 330includes a sliding pivot joint 312 that allows the second jaw 306 topivot about a point that is translatable with respect to the first jaw302. For example, the sliding pivot joint 312 can comprise a pivotingpin disposed in a slot formed in the first jaw 302.

With continued reference to FIGS. 20-23, the second guide slot 320disposed in the second jaw 306 can comprise an opening segment adjacenta proximal end of the second guide slot and a firing transition segmentdistal the opening segment. Distal movement of the actuation member 350distally advances the second guide 316 along the opening segment of thesecond guide slot 320 to slide the second jaw 306 away from the firstjaw 302 and pivot the second jaw 306 into the open configuration (FIGS.21-22). Further distal movement of the actuation member distallyadvances the second guide 316 past the firing transition segment andinto a firing segment extending generally longitudinally along thesecond jaw 306 to position the jaw assembly 330 in a firingconfiguration (FIGS. 23-24).

With reference to FIG. 25-31, an embodiment of jaw assembly 430 with aslotted actuator for use in a surgical stapler 10 is illustrated. In theillustrated embodiment, the jaw assembly 430 comprises a first jaw 402having a first clamping surface 404 and comprising a first guide slot418, a link 412, and a second jaw 406 having a second clamping surface408 and comprising a second guide slot 420. An actuation member 450 orbeam comprising a first guide 414 and a second guide 416 can actuate thejaw assembly 430 from the closed configuration (FIGS. 25-27), to theopen configuration (FIGS. 28-29) to the firing or stapling configuration(FIGS. 30-31) in a sequence of operation similar to those describedabove with respect to the jaw assemblies 130, 230.

With reference to FIGS. 27-29, the link 412 can include a third guide426 thereon, such as one or more pins, tabs, or posts extendingtherefrom. The actuation member 450 can include a third guide slot 424formed therein. The third guide 426 of the link 412 can be slideablyengaged in the third guide slot 424. The third guide slot 424 cancomprise an opening segment and a firing transition segment which extendtransverse to the longitudinal axis. When the actuation member 450 isadvanced distally from an initial position, the third guide 426 of thelink 412 passes through the opening segment such that the link 412 ispivoted away from the first jaw 402 (FIGS. 28-29). Continued translationof the actuation member 450 advances the third guide 426 of the link 412past the firing transition segment of the third guide slot 424 toposition the second jaw 406 in the firing position (FIGS. 30-31).

With reference to FIGS. 32-38, another embodiment of jaw assembly 530for use with a surgical stapler 10 is illustrated. In the illustratedembodiment, the jaw assembly 530 comprises a first jaw 502 having afirst clamping surface 504 and comprising a first guide slot 518, a link512 comprising a second guide slot 520, and a second jaw 506 having asecond clamping surface 508 and comprising a third guide slot 522. Anactuation member 550 or beam comprising a first guide 514 and a secondguide 516 can actuate the jaw assembly 530 from the closed configuration(FIGS. 32-34), to the open configuration (FIGS. 35-36) to the firing orstapling configuration (FIGS. 37-38) in a sequence of operation similarto those described above with respect to the jaw assemblies 130, 230,430.

With reference to FIGS. 34-36, in the illustrated embodiment, theactuation member 550 can include a first guide 514 positioned at adistal end of a first arm or extension and a second guide positioned ata distal end of a second arm or extension. The first and second arms canbe flexibly coupled to one another such that a distance between thefirst guide 514 and the second guide 516 can be varied. The first andsecond arms can be biased away from one another. Advantageously, thevariable spacing of the first guide 514 and second guide 516 can allowpositioning of the third guide slot 522 in a position relatively closeto an outer surface opposite the second clamping surface 508 of thesecond jaw 506. Accordingly, additional working space in the second jawadjacent the second clamping surface can be freed by positioning thethird guide slot 522 closer to the outer surface.

Although this application discloses certain preferred embodiments andexamples, it will be understood by those skilled in the art that thepresent inventions extend beyond the specifically disclosed embodimentsto other alternative embodiments and/or uses of the invention andobvious modifications and equivalents thereof. Further, the variousfeatures of these inventions can be used alone, or in combination withother features of these inventions other than as expressly describedabove. Thus, it is intended that the scope of the present inventionsherein disclosed should not be limited by the particular disclosedembodiments described above, but should be determined only by a fairreading of claims which follow.

What is claimed is:
 1. A surgical stapler comprising: an elongate shafthaving a proximal end and a distal end and defining a longitudinal axisbetween the proximal end and the distal end; a handle assembly disposedat the proximal end of the elongate shaft; an actuation mechanismactuatable by the handle assembly, the actuation mechanism comprising anactuation beam longitudinally slidable in the elongate shaft, theactuation beam comprising a first guide and a second guide formedthereon; and a jaw assembly disposed at the distal end of the elongateshaft, the jaw assembly comprising: a first jaw defining a firstclamping surface, the first jaw comprising a first guide slot extendinglongitudinally therein, the first guide of the actuation beam slidablypositioned in the first guide slot; a second guide slot comprising anopening segment and a firing transition segment, the second guide of theactuation beam slidably positionable in the second guide slot; a secondjaw defining a second clamping surface, the second jaw comprising athird guide slot extending longitudinally therein, the second guide ofthe actuation beam slidably positionable in the third guide slot; and aplurality of staples positioned in the first jaw, wherein the jawassembly is actuatable by longitudinal movement of the actuation beambetween a closed position in which the first clamping surface contactsthe second clamping surface, an open position in which the secondclamping surface extends at an angle transverse to the first clampingsurface, and a stapling position in which the first clamping surfaceextends parallel to the second clamping surface and is spaced apart fromthe second clamping surface.
 2. The surgical stapler of claim 1, whereinthe second guide slot further comprises a closed segment proximal theopening segment.
 3. A surgical stapler comprising: an elongate shafthaving a proximal end and a distal end and defining a longitudinal axisbetween the proximal end and the distal end; a handle assembly disposedat the proximal end of the elongate shaft; an actuation mechanismactuatable by the handle assembly, the actuation mechanism comprising anactuation beam longitudinally slidable in the elongate shaft, theactuation beam comprising a first guide and a second guide formedthereon; and a jaw assembly disposed at the distal end of the elongateshaft, the jaw assembly comprising: a first jaw defining a firstclamping surface, the first jaw comprising a first guide slot extendinglongitudinally therein, the first guide of the actuation beam slidablypositioned in the first guide slot; a second guide slot comprising anopening segment and a firing transition segment, the second guide of theactuation beam slidably positionable in the second guide slot; a secondjaw defining a second clamping surface, the second jaw comprising athird guide slot extending longitudinally therein, the second guide ofthe actuation beam slidably positionable in the third guide slot; and aplurality of staples positioned in the first jaw, wherein the jawassembly further comprises a link having a proximal end and a distalend, the proximal end of the link pivotably coupled to the distal end ofthe elongate shaft, and the distal end of the link pivotably coupled toa proximal end of the second jaw, the second guide slot disposed in thelink.
 4. The surgical stapler of claim 3, wherein the link is biasedaway from the first jaw.
 5. A surgical stapler comprising: an elongateshaft having a proximal end and a distal end and defining a longitudinalaxis between the proximal end and the distal end; a handle assemblydisposed at the proximal end of the elongate shaft; an actuationmechanism actuatable by the handle assembly, the actuation mechanismcomprising an actuation beam longitudinally slidable in the elongateshaft, the actuation beam comprising a first guide and a second guideformed thereon; and a jaw assembly disposed at the distal end of theelongate shaft, the jaw assembly comprising: a first jaw defining afirst clamping surface, the first jaw comprising a first guide slotextending longitudinally therein, the first guide of the actuation beamslidably positioned in the first guide slot; a second guide slotcomprising an opening segment and a firing transition segment, thesecond guide of the actuation beam slidably positionable in the secondguide slot; a second jaw defining a second clamping surface, the secondjaw comprising a third guide slot extending longitudinally therein, thesecond guide of the actuation beam slidably positionable in the thirdguide slot; and a plurality of staples positioned in the first jaw,wherein the opening segment has an angular profile oriented such thatdistal sliding of the second guide through the second guide slot pivotsthe second jaw away from the first jaw to position the jaw assembly inan open position.
 6. The surgical stapler of claim 5, wherein furtherdistal advancement of the actuation beam advances the second guide overthe firing transition segment of the second guide slot to pivot thesecond jaw to a position spaced apart from the first jaw a predetermineddistance.
 7. A surgical stapler comprising: an elongate shaft having aproximal end and a distal end and defining a longitudinal axis betweenthe proximal end and the distal end; an actuation beam longitudinallyslidable in the elongate shaft, the actuation beam comprising a firstguide and a second guide formed thereon; and a jaw assembly disposed atthe distal end of the elongate shaft, the jaw assembly comprising: afirst jaw defining a first clamping surface, the first jaw comprising afirst guide slot extending longitudinally therein; a link having aproximal end pivotably coupled to the distal end of the elongate shaftand a distal end opposite the proximal end, the link comprising a secondguide slot formed therein, the second guide slot comprising an openingsegment and a firing transition segment; and a second jaw defining asecond clamping surface, the second jaw pivotably coupled to the distalend of the link, the second jaw comprising a third guide slot extendinglongitudinally therein.
 8. The surgical stapler of claim 7, wherein thesecond guide slot further comprises an initial closed segment proximalthe opening segment.
 9. The surgical stapler of claim 7, wherein thesecond jaw further comprises a pivotal stop that prevents excesspivoting of the second jaw relative to the first jaw.
 10. The surgicalstapler of claim 7, wherein the jaw assembly further comprises a springbiasing the link away from the first jaw.
 11. The surgical stapler ofclaim 7, wherein the jaw assembly further comprises a spring biasing thesecond jaw away from the first jaw.
 12. The surgical stapler of claim 7,wherein the actuation beam has a distal end and wherein the distal endof the actuation beam comprises an !-beam cross sectional profile. 13.The surgical stapler of claim 7, wherein the opening segment of thesecond guide slot has a profile oriented such that distal sliding of thesecond guide distally through the opening segment pivots the link awayfrom the first jaw.